Connective tissue disease type mediates branch patency of grafts in open thoracoabdominal aortic reconstruction

Objective: Despite a shared degenerative vascular phenotype, Marfan syndrome (MFS), Loeys-Dietz syndrome (LDS), and other genetically distinct connective tissue diseases (CTDs) have unique extravascular pathologies that impact the outcomes of aortic replacement. The aim of our study was to investigate the association of CTD genotype with postoperative outcomes and branch patency following open thoracoabdominal aortic replacement in a large institutional cohort. Methods: All patients undergoing open branched thoracoabdominal aortic replacement at a single academic center from 2006 to 2020 were included and classified as CTD or non-CTD based on the presence of genotypic documentation. Outcomes were compared using analysis of variance and χ² testing for continuous and discrete variables, respectively. Kaplan-Meier curves were utilized to examine patency of graft branches over time. Results: Overall, 172 patients were included, with a mean follow-up of 30.5 ± 34.9 months. CTD was present in 45 patients (26%); specifically, 32 had MFS, five had LDS, and eight had another CTD. Patients with CTDs had more extent II thoracoabdominal aneurysms (40% vs 15%), more reconstructed branches (3.5 vs 1.8), more frequently reconstructed visceral branches (86.7% vs 22.7%), and higher intraoperative blood loss (13.3 vs 6.8 L; all P <.05) compared with non-CTD patients. Patients with MFS were more frequently systemically anticoagulated preoperatively (50% vs 5%) and demonstrated higher rates of postoperative deep vein thrombosis/pulmonary embolism compared with non-CTD patients (9% vs 2%; both P <.05). Five-year renal branch patency was decreased among all patients compared with visceral branches (87.3% vs 95.6%; P =.05), but there were no individual branch patency differences between patients with and without CTDs (P =.086). Overall branch patency at 1 and 5 years was significantly higher in patients with MFS than in non-CTD patients (98.9% vs 89.1% at 5 years); there were no significant patency differences between non-CTD patients and any other CTD subgroup, mostly due to early patency loss. Conclusions: Open thoracoabdominal reconstruction in patients with CTD is technically challenging and associated with increased transfusion and postoperative thromboembolic events when compared with non-CTD patients. Technical outcomes of the procedure are excellent and are differentially associated with genotype, with patients with MFS experiencing significantly improved branch patency over both non-CTD patients and patients with other CTDs, a finding which has multifactorial drivers.